feat: Expose wildcard and sanity checks on Descriptor

Author: ItoroD

CHANGELOG.md

@@ -4,6 +4,11 @@ Changelog information can also be found in each release's git tag (which can be
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/), and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased](https://github.com/bitcoindevkit/bdk-ffi/compare/v2.3.0...HEAD)
+
+### Added
+- Expose miniscript `has_wildcard` and `sanity_check` methods on `Descriptor` type #945
+
 ## [v2.3.0]
 
 This is version `2.3.0` of the BDK language bindings! This release uses the following Rust dependencies:

bdk-android/lib/src/androidTest/kotlin/org/bitcoindevkit/DescriptorTest.kt

@@ -2,8 +2,11 @@ package org.bitcoindevkit
 
 import kotlin.test.Test
 import androidx.test.ext.junit.runners.AndroidJUnit4
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
 import org.junit.runner.RunWith
 import kotlin.test.assertFails
+import kotlin.test.assertFailsWith
 
 @RunWith(AndroidJUnit4::class)
 class DescriptorTest {
@@ -47,4 +50,30 @@ class DescriptorTest {
             )
         }
     }
+
+    @Test
+    fun sanityCheck() {
+        val safeDescriptor = Descriptor("multi(1,L4rK1yDtCWekvXuE6oXD9jCYfFNV2cWRpVuPLBcCU2z8TrisoyY1,5KYZdUEo39z3FPrtuX2QbbwGnNP5zTd7yyr2SC1j299sBCnWjss)", Network.BITCOIN)
+
+        safeDescriptor.sanityCheck()
+
+        //multi(2, key1, key1)) is structurally valid but unsafe
+        val unsafeDescriptor = Descriptor("multi(2,L4rK1yDtCWekvXuE6oXD9jCYfFNV2cWRpVuPLBcCU2z8TrisoyY1,L4rK1yDtCWekvXuE6oXD9jCYfFNV2cWRpVuPLBcCU2z8TrisoyY1)", Network.BITCOIN)
+
+        // descriptor failed as expected because it uses the same public key twice in a 2 of 2 multisig
+        assertFailsWith<DescriptorException.Miniscript> {
+            unsafeDescriptor.sanityCheck()
+        }
+    }
+
+    @Test
+    fun checkDescriptorWildcard(){
+        val wildcardDescriptor = Descriptor("wpkh($TEST_EXTENDED_PRIVKEY/$BIP84_TEST_RECEIVE_PATH/*)", Network.REGTEST)
+        val nonWildcardDescriptor = Descriptor("wpkh($TEST_EXTENDED_PRIVKEY/$BIP84_TEST_RECEIVE_PATH/0)", Network.REGTEST)
+
+        assertTrue(wildcardDescriptor.hasWildcard())
+
+        assertFalse(nonWildcardDescriptor.hasWildcard())
+    }
+
 }

bdk-ffi/src/descriptor.rs

@@ -384,6 +384,28 @@ impl Descriptor {
 
         Ok(Arc::new(address))
     }
+
+    /// Whether or not the descriptor has any wildcards.
+    pub fn has_wildcard(&self) -> bool {
+        self.extended_descriptor.has_wildcard()
+    }
+
+    /// Checks whether the descriptor is safe.
+    ///
+    /// Checks whether all the spend paths in the descriptor are possible on the
+    /// bitcoin network under the current standardness and consensus rules. Also
+    /// checks whether the descriptor requires signatures on all spend paths and
+    /// whether the script is malleable.
+    ///
+    /// In general, all the guarantees of miniscript hold only for safe scripts.
+    /// The signer may not be able to find satisfactions even if one exists.
+    pub fn sanity_check(&self) -> Result<(), DescriptorError> {
+        self.extended_descriptor
+            .sanity_check()
+            .map_err(|e| DescriptorError::Miniscript {
+                error_message: e.to_string(),
+            })
+    }
 }
 
 impl Display for Descriptor {